The present invention relates to a system and method for controlling wireless network access.
In an existing wireless network, a number of base stations that are geographically spaced apart from each other are connected to a wireless switching center. Each base station is equipped with a transceiver for communicating with wireless devices within the range of that base station. The wireless devices or subscriber units each have a unique device identity.
Generally, when a subscriber unit is turned on, the subscriber unit transmits its device identity. The nearest base station receives the device identity, and is thus informed of the presence of that particular subscriber unit. As such, the subscriber unit may travel through different geographic locations, passing through the receiving zones of several different base stations, with each base station detecting the subscriber unit by receiving the periodically transmitted device identity. Because there are multiple service providers, a subscriber unit may sometimes pass from one provider""s service area to another provider""s service area, while continuing to transmit its device identity.
Another existing wireless device technology used in some personal communication systems utilizes channel scanning before transmission. A device in such a system will first look for an open channel, and upon finding one will begin transmitting.
Although such arrangements have been used in many applications that are commercially successful, particularly for mobile wireless applications, that success is founded upon the cooperation of the many different providers. As such, these existing subscriber units may be somewhat undesirable if one of the providers does not want to be receiving over-the-air transmissions from other providers"" subscriber units (or if such transmissions would violate FCC regulation for the frequencies in use), as the case may be for fixed wireless applications.
For the foregoing reasons, there is a need for a system and method for controlling wireless network access that overcomes the problems and limitations of the prior art.
It is, therefore, an object of the present invention to provide a system and method for controlling wireless network access that utilizes listen-before-talk techniques such that the subscriber unit only transmits when the base station allows such transmission.
In carrying out the above object, and other objects, features, and advantages of the present invention, a method for controlling wireless network access for a wireless user subscriber unit having a preferably unique device identity is provided. The method comprises listening with the user subscriber unit, and transmitting a set of device identities corresponding to a set of valid subscriber units from a base station. The method further comprises, upon receiving the device identity corresponding to the user subscriber unit at the user subscriber unit, transmitting a request for network access with the user subscriber unit. In a preferred embodiment, each device identity is an electronic serial number (ESN).
Further, in a preferred embodiment, the method comprises granting network access to the user subscriber unit upon receiving the request for network access at the base station. Further, preferably, transmit power of the user subscriber unit is controlled by the base station. Further, preferably, the base station may send a terminate request to the subscriber unit, and in response, the user subscriber unit and the base station discontinue transmissions between each other. Transmissions are discontinued upon the terminate request being received at the user subscriber unit. Preferably, the user subscriber unit will autonomously cease transmissions after expiring of a timer if the subscriber unit ceases to receive permission from the base station.
Further, preferably, the user subscriber units may send a terminate request to the base station. Accordingly, transmissions between the user subscriber unit and the base station are discontinued upon the base station receiving the terminate request.
Still further, in a preferred embodiment, a plurality of sets of device identities are transmitted from a corresponding plurality of base stations. The set of device identities that is transmitted from a particular base station is based on a location of the particular base station. As such, each base station transmits device identities of those devices that are permitted to transmit when within range of that base station.
Further, in one embodiment, the base station transmits a first set of device identities corresponding to a first set of valid subscriber units on a generally periodic basis with a first period. Further, the base station transmits a second set of device identities corresponding to a second set of valid subscriber units from the base station on a generally periodic basis with a second period. The second period is different than the first period. That is, one set of device identities may be transmitted more often than the other set of device identities when one group of valid subscriber units is expected to require access more often than the other group of subscriber units. Further, there may be any number of different device identity sets and periods that may be used to increase or decrease responsiveness to subscriber access based on subscriber activity or other parameters that the service provider may implement such as time of day, network load, priorities, etcetera.
Further, a preferred method comprises granting a specified amount of time for response from the set of valid subscriber units upon transmitting the set of device identities. The request for network access must then be transmitted by the user subscriber unit within the specified amount of time.
Further, in carrying out the present invention, a method for controlling wireless network access for a wireless user subscriber unit having a device identity is provided. The method comprises listening with the user subscriber unit, transmitting a set of device identities corresponding to a set of valid subscriber units from a base station, and granting a specified amount of time for response from the set of valid subscriber units upon transmitting the set of device identities. The method further comprises, upon receiving the device identity corresponding to the user subscriber unit, transmitting a request for network access from the user subscriber unit within the specified amount of time. Network access is granted to the user subscriber unit by the base station upon receiving the request for network access at the base station.
Still further, in carrying out the present invention, a system for controlling wireless network access is provided. The system comprises a user subscriber unit and a base station. The user subscriber unit is configured to listen for a (preferably unique) device identity corresponding to the user subscriber unit. The user subscriber unit is further configured to transmit a request for network access upon receiving the device identity corresponding to the user subscriber unit, when network access is desired. The base station is configured to transmit a set of device identities corresponding to a set of valid subscriber units.
In a preferred system, the base station is further configured to grant a specified amount of time for response from the set of valid subscriber units upon transmitting the set of device identities. Further, the base station is configured to grant network access to the user subscriber unit upon receiving the request for network access at the base station within the specified time for response.
Yet further, in carrying out the present invention, a wireless user device for use in a fixed, portable, or mobile wireless network is provided. In the fixed, portable, or mobile wireless network, the user wireless device is permitted to access the network when the user wireless device is within a pre-selected fixed region with at least one operational base station in the region to permit network access. Network access is permitted for a predetermined plurality of wireless devices including the user wireless device.
The user wireless device comprises a user subscriber unit configured to listen for a device identity corresponding to the user subscriber unit. The device identity is transmitted along with a plurality of other device identities corresponding to other wireless devices by at least one base station. The user subscriber unit is further configured to transmit a request for network access after receiving the device identity corresponding to the user subscriber unit, when network access is desired. Alternatively, a set of valid device identities could be indicated by the broadcasting of an exception list. That is, all subscriber units except those in the exception list may access the network.
The advantages associated with embodiments of the present invention are numerous. For example, embodiments of the present invention propose a non-interfering wireless access scheme in which each base station periodically transmits the device identity of valid subscriber units in the network. Reception of its own device identity from the base station allows the subscriber unit to request wireless access on an as-needed basis. As such, embodiments of the present invention provide wireless access while minimizing potential interference to other service providers, and eliminating the potential for violating FCC regulations in frequency bands where transmission in other service provider""s territory is strictly forbidden.
Additionally, embodiments of the present invention may be configured to divide the broadcasts of device identities into local and roaming lists. This permits differentiation in how lists for local users are maintained from those that are roaming to increase efficiency and responsiveness.
The above object and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.